Location: Corn, Soybean and Wheat Quality Research
2022 Annual Report
Objectives
Objective 1: Develop accurate and efficient testing methods for processing and marketing quality of soft winter (SW) wheat.
Sub-objective 1a. Develop simple and fast methods for the estimation of wheat grain PHS.
Sub-objective 1b. Improve the existing cracker baking test to make it easier and more widely useable.
Objective 2: Identify SW wheat varieties with various quality characteristics for new food uses.
Sub-objective 2a. Determine the suitability of eastern SW wheat for making tortillas and identify the required quality characteristics.
Sub-objective 2b. Determine the suitability of eastern SW wheat for making white salted noodles and identify the required quality characteristics.
Sub-objective 2c. Develop and evaluate partial and full waxy wheat germplasms for new use.
Objective 3: Develop markers for pre-harvest sprouting using a diverse SW wheat population.
Sub-objective 3a. Find Eastern SW wheat varieties closely related genetically that differ in PHS resistance.
Sub-objective 3b. Locate regions for PHS resistance using a Genome-Wide Association Study (GWAS) on a diverse panel of SW wheat with genotype-by-sequencing (GBS) markers.
Sub-objective 3c. Uncover genes differentially expressed under conditions conducive to PHS versus non-conducive comparing results between lines that are resistant or susceptible to PHS.
Sub-objective 3d. Develop markers for resistance to PHS.
Objective 4: Evaluate and report the milling (processing and intrinsic end-use quality) parameters of SW wheat commercially viable cultivars.
Approach
The Soft Wheat Quality Laboratory (SWQL) aims to improve the end-use quality, uses and marketability of soft winter (SW) wheat in the eastern U.S. by contributing to the development of wheat varieties of improved end-use quality potential and developing new food uses. To attain this goal, the SWQL works to develop reliable and efficient quality testing methods, performs fundamental research on grain characteristics and genetics associated with quality traits, explores potentials of eastern soft wheat for extended uses and performs the comprehensive evaluation of breeding lines for end use quality. The project plan encompasses the effective evaluation of pre-harvest sprouting (PHS) damage and cracker baking quality potential, extended use potentials for tortillas and noodles, genetic factors controlling PHS, and milling and baking quality evaluation of SW wheat, which are crucial for the quality improvement and extended uses of eastern SW wheat.
The required quality characteristics and suitability of eastern SW wheat grain for making tortillas and soft-bite wheat salted noodles will be identified and demonstrated, respectively. Development of partial and full waxy wheat germplasms will be continued, and their potential uses including tortilla and noodles will be examined.
The identification of genetic factors controlling PHS and development of markers for PHS resistance will be conducted in four phases: 1) identify eastern SW wheat varieties closely related genetically that differ in PHS resistance; 2) locate regions for PHS resistance using a Genome-Wide Association Study (GWAS) on a diverse panel of SW wheat with genotype-by-sequencing markers; 3) identify genes differentially expressed under conditions conducive to PHS versus non-conducive comparing results between lines that are resistant or susceptible to PHS; and 4) develop markers for PHS resistance from GWAS and expression analysis.
To contribute to the development of wheat varieties of improved end-use quality potential, the annual evaluation of eastern SW wheat breeding lines for defined milling and baking quality characteristics wil be conducted in collaboration with eastern SW breeding programs.
Progress Report
This project aimed to improve the milling and baking quality of eastern soft wheat varieties by developing accurate and reliable quality testing methods, identifying the biochemical and genetic characteristics of wheat important for extended uses, and contributing to the development of wheat varieties by conducting the end-use quality evaluation of wheat breeding lines.
Objective 1, develop accurate and efficient testing methods to determine the processing and marketing quality of soft winter (SW) wheat. The fluidity/viscosity of a whole wheat meal hot paste is affected considerably by alpha-amylase activity (which rapidly increases during grain sprouting), and thus is an effective indicator of wheat grain pre-harvest sprouting (PHS). The falling number (FN) test relies on the hot paste viscosity of whole grain meal and is considered as the industry standard test for wheat grain PHS, but it is a low throughput test that requires expensive equipment. The hot paste flow distance determined using a Bostwick consistometer depends primarily on its viscosity and could be a simple and fast alternate to FN for PHS estimation. Whole meal to water ratio, heating time of paste and paste flow time in the hot paste flow distance test were optimized to facilitate the test and yield the best differentiation of wheat grains known to be different in FN and degree of pre-harvest sprouting. For a set of 15 grain samples with a wide range of PHS damage, the paste flow distance of whole grain meals showed a strong relationship with FN with 97% predictability, proving that the approach could be developed as a method to provide a more simple and quick assessment of wheat grain PHS than the FN test.
The pasta dough sheeter and noodle maker, which were identified as potential replacements for the currently used, heavy and not commonly available dough sheeter, deliver a weaker sheeting force than the latter and often fail to yield a single piece of dough, requiring an adjustment of the water amount added to the dough. With a fixed amount of water as in the current method, some wheat flours produced doughs that were too wet and weak to avoid unwanted drooping during sheeting, while others were too dry to produce a single, continuous dough sheet, suggesting that the optimal water amount needs to be identified and used in the preparation of cracker dough. Three eastern soft wheat flours widely different in protein characteristics required 28 to 34 g water per 100 g wheat flour to yield crumbly dough of pea size pieces and a continuous dough sheet when sheeted using the pasta dough sheeter and noodle maker. With the use of optimal water level for the preparation of cracker dough, the new pasta dough sheeter and noodle maker produced a cracker dough sheet of comparable thickness to the currently used sheeter. All three sheeters produced a dough sheet and cracker of acceptable quality when the optimal amount of water was used, and effectively differentiated three flours of varying protein characteristics in cracker quality parameters.
Objective 2, identify SW wheat varieties with various quality characteristics for new food uses. Thirty-nine SW wheat varieties were analyzed for wet gluten content and dough rheological properties and compared to commercial tortilla flours. As expected from their protein contents and strengths estimated previously by lactic acid solvent retention capacity and sodium dodecyl sulfate sedimentation volume, SW wheat varieties varied widely in gluten content and dough mixing and extensibility properties. Only nine eastern SW wheat varieties out of 39 had high enough wet gluten contents to be comparable to five commercial tortilla flours. For dough extension force, only one SW wheat variety was comparable to commercial flour, indicating that the protein contents and strengths of SW wheat varieties are generally lower than those of commercial tortilla flours. SW wheat carrying protein of high content and strength would be the appropriate choice for making tortillas.
In addition to the grain, milling and flour compositional characteristics determined in the previous year, 25 SW wheat varieties were further analyzed for solvent retention capacities (SRCs), protein strength using the SDS sedimentation (SDSS) test, hot paste viscosity and dough mixing properties, and were compared to four commercial noodle flours from Japan and Korea. The lactic acid SRC and SDSS ranges of SW wheat flours encompassed those of commercial noodle flours with the latter being on the high side, indicating that the SW wheat varieties of high lactic acid SRC and SDSS are desirable for making white salted noodles (WSN). The SW wheat varieties exhibited a lower mixograph dough mixing time (which is a measure of gluten protein strength) than the commercial noodle flours, indicating that the selection of SW varieties with strong gluten protein is required for making noodles. SW wheat flours showed generally lower water retention capacities than commercial noodle flours, which was likely due to the lower protein content and damaged starch content of the former. The commercial noodle flours exhibited distinctively lower starch amylose contents and consequently higher starch paste viscosities than the SW wheat flours, indicating that the introduction of a partial waxy trait, which lowers the starch amylose content, to the SW wheat varieties would enhance their WSN making quality.
Eleven to 12 waxy, two to four single-null (B genome) partial waxy and two to three double-null (A and D genomes) partial waxy wheat germplasms of cultivars Kristy and Wilson backgrounds were selected based on their agronomic performances in 2021 for the determination of grain yield potential and disease resistance. Those selected waxy and partial waxy wheat germplasms were planted in the fall of 2021 in Wooster, Ohio, and have been grown for grain yield potential and disease resistance determination in comparison to four commercial soft red winter wheat varieties. The six partial waxy wheat lines of cultivars Kristy and Wilson backgrounds, including one from each of three double-null and three single-null partial waxy genotypes selected based on their amylose content, were planted in Wooster, Ohio, in the fall 2021 and have been grown for grain increase. The harvested partial waxy wheats will be used for the evaluation of flour characteristics, starch properties and their quality potentials for making tortillas, noodles and steamed bread.
Objective 3, develop markers for pre-harvest sprouting using a diverse SW wheat population. Placed 1,978 genetic markers on the association mapping population. Markers were used to identify four pairs of varieties that were closely related where one individual of the pair was susceptible to pre-harvest sprouting and the other resistant. Manuscript submitted with the markers and a case study using them.
Whole genome expression on pairs of genetically similar soft winter wheat varieties that differ in pre-harvest sprouting resistance was studied. This will help scientists better understand what genes are involved in pre-harvest sprouting. RNA was collected from 63 samples, high quality gene libraries of each sample developed, and adapters added for sequencing. The libraries were sent to a USDA-ARS sequencing center in Stoneville, Mississippi for sequencing to complete the analysis as part of next year’s milestone.
Developed scripts of a recently published genome-wide association tool to automate annotation of chromosome locations significantly involved in traits such as pre-harvest sprouting or insect resistance. Tool further modified for use in wheat and a genome-wide association study of 24 agronomic, flour quality, and preharvest sprouting resistance traits completed. Study measured data over 4 years on 188 diverse varieties of soft winter wheat using the 1,978 genetic marker set. Twenty-three chromosome locations for pre-harvest sprouting resistance found as part of 168 locations of 223 total trait effects. Other traits for flour quality, seed color, plant height, heading date, and years since release of breeding variety were utilized to understand the effect of breeding over time and how much pre-harvest sprouting resistance locations overlapped other traits. Only two pre-harvest sprouting resistance locations overlapped other traits. Thus, wheat breeders could add pre-harvest sprouting resistance to newly bred soft winter wheat varieties without impacting other agronomic and milling and baking traits.
Objective 4, evaluate and report the milling parameters of SW wheat commercially viable cultivars. The comprehensive milling and baking quality evaluations for 3,749 samples harvested in 2021 and submitted by nine public and private eastern soft wheat breeding programs, seven uniform regional performance trials and three research collaborators have been completed. The test results were summarized, analyzed, and shared with the breeding programs with suggestions, directly contributing to the development of new wheat varieties possessing superior quality. We coordinated the Soft Wheat Quality Council (SWQC) Project for the annual evaluation of new varieties and advanced breeding lines by managing the entry grow-outs in three locations, procuring wheat grain samples, carrying out pilot-scale milling, distributing flour samples to collaborators, performing quality trait evaluations, and preparing a report that collates quality evaluations among the collaborators for presentation at the annual SWQC Meeting. We participated in the Pacific Northwest Wheat Quality Project and Michigan State University Wheat Quality Testing Project and performed the comprehensive evaluation of advanced breeding lines and varieties for flour characteristics and baking quality.
Accomplishments
1. Eastern soft wheat (SW) germplasms yielding extra soft grain, producing better quality flour and products. Kernel hardness is an important quality trait for soft wheat because it directly influences flour particle size, starch damage, water absorption and product quality. Soft textured grain is produced from wheat varieties carrying functional genes on chromosome 5D (Pin5D genes). ARS scientists in Wooster, Ohio, developed wheat germplasms producing even softer wheat grains by adding functional Pin5A genes to two SW varieties and evaluated their influence on grain and flour characteristics and cookie-baking quality. The wheat germplasms with Pin5A genes produced wheat grains of considerably softer texture, which yielded wheat flour of much finer particle size when milled, and subsequently baked cookies with larger diameters compared to the varieties without Pin5A genes, providing wheat breeders with an effective tool to improve the milling and cookie-baking quality of eastern SW. The knowledge on the role of Pin5A genes in wheat grain hardness and eastern SW germplasms of extra soft grain characteristics will provide wheat breeders with the direction and essential genetic resources, respectively, needed for the development of wheat varieties carrying uniquely desirable grain characteristics.
2. Identification of grain, flour and batter characteristics that estimate cake baking quality. Cakes are generally prepared from soft wheat flour of fine particle size, low protein content and low damaged starch content; however, these characteristics vary widely among wheat varieties. The fast and reliable estimation of wheat flour quality for baking cakes is crucial in screening breeding lines in variety development and in the procurement of grain and flour by millers and bakers. Wheat flour quality for baking cakes is assessed by conducting an experimental cake baking test, which is inefficient and laborious. ARS scientists in Wooster, Ohio identified that the water or sucrose solvent retention capacities of flour are effective indicators of cake baking quality. Furthermore, viscosities of the batter prepared from just flour and water, or flour, sucrose and water also differed widely among flours of different characteristics and all were correlated to cake volume. Flour-sucrose viscosity is expected to be more effective in the estimation of cake baking quality than flour-water viscosity, whereas the latter is much easier to prepare. The identification of these effective tools for cake baking quality estimation will greatly help wheat breeders in the screening of breeding lines for high cake baking quality and millers and bakers in the identification and procurement of wheat and flour suitable for baking cakes.
3. Genetic variations in developmental genes of eastern U.S. soft winter and Korean winter wheat varieties and their associations with heading date. Early heading (emergence of ear) leads to early maturation and harvesting of wheat, which allows the planting of soybean with minimal delay in the wheat-soybean double cropping system. The heading time of wheat depends on climatic conditions including temperature and day length, and genes that govern the cold temperature requirement at the seedling stage (vernalization) and the day length requirement (photoperiod) for flowering. Knowledge on the variation in these genes and their effects on heading date would provide a valuable tool for wheat breeders. ARS scientists in Wooster, Ohio identified the genes and gene profiles that provide the early-heading trait by determining the variation in heading time-related genes of 149 eastern SW and 32 Korean wheat varieties and assessing their effects in eastern U.S. environments. Eastern SW varieties headed on average 14 days later than Korean wheat varieties. Ninety-four percent of eastern SW varieties carried three or more copies of the vernalization gene related to late heading, whereas 81.3% of Korean wheat varieties carried one copy of the vernalization gene contributing to early heading. Early-heading and early-maturing were achieved by the combination of a single copy of the vernalization gene on chromosome 1A, the other vernalization gene associated with early-heading on chromosome 3D and photoperiod insensitive genes. The obtained results provide eastern U.S. wheat breeding programs with genetic resources necessary for the development of early-maturing wheat varieties suitable for the wheat-soybean double-cropping.
Review Publications
Ibrahim, A.M., Sutton, R., Johnson, J.W., Mergoum, M., Simoneaux, B., Harrison, S.A., Murphy, J.P., Mason, R.E., Baber, M.A., Neely, C., Opena, G., Jin, Y., Kolmer, J.A., Boyles, R., Cambron, S.E., Baik, B.V., Brown Guedira, G.L., Marshall, D.S., Fountain, M.O. 2021. Registration of 'GA06343-13E2 (TX-EL2)' soft red winter wheat. Journal of Plant Registrations. 15(1):107-112. https://doi.org/10.1002/plr2.20031.
Mergoum, M., Johnson, J.W., Sutton, S., Lopez, B., Bland, D., Chen, Z., Buntin, G.D., Mailhot, D.J., Babar, M.A., Mason, R.E., Harrison, S.A., Murphy, J.P., Ibrahim, A.M., Sutton, R., Simoneaux, B.E., Griffey, C.A., Bockelman, H.E., Baik, B.V., Marshall, D.S., Cowger, C., Brown Guedira, G.L., Kolmer, J.A., Jin, Y., Cambron, S.E. 2021. ‘GA JT141-14E45’: A new soft red winter wheat cultivar adapted to Georgia and the south east US environments. Journal of Plant Registrations. 15:471-478. https://doi.org/10.1002/plr2.20070.
Baik, B.V., Donelson, T.S. 2022. Grain, flour and batter properties estimating cake baking potential of wheat flour. Cereal Chemistry. Article 10560. https://doi.org/10.1002/cche.10560.
Ma, F., Lee, Y., Park, E., Luo, Y., Delwiche, S.R., Baik, B.V. 2021. Influences of hydrothermal and pressure treatments of wheat bran on the quality and sensory attributes of whole wheat Chinese steamed bread and pancakes. Journal of Cereal Science. 102. Article 103356. https://doi.org/10.1016/j.jcs.2021.103356.
Ma, F., Sturbaum-Abud, A.K., Baik, B.V. 2021. Registration of ten soft red winter waxy wheat germplasm lines. Journal of Plant Registrations. 16:147-151. https://doi.org/10.1002/plr2.20151.
Hill, M.J., Penning, B., Mccann, M.C., Carpita, N.C. 2022. COMPILE: A GWAS computational pipeline for gene discovery in complex genomes. BMC Plant Biology. 22:Article 315. https://doi.org/10.1186/s12870-022-03668-9.
